We're going to turn to the concussion cry kr sis in the NFL. Dan Marino has joined others suing the league. He is among those that claims the league didn't come clean with the dangers about concussion. And Jim Avila is here with more. Reporter: New problems for the NFL. One of its biggest stars says in a lawsuit, he may have suffered long-term effects from violence in the game and dangers the league ignored. There have been big names before. Brett Favre. Tony Dorsett. Jim Mcmahon and junior sea. But today, the biggest name of them all. Hall of fame quarterback, Dan Marino. Now suing the league, along with 14 other former players for damage they claim resulted from hard hits to the head. This makes this human. It makes it real. And it makes it famous. And that's a very big deal. Reporter: The NFL has already agreed to pay former players $750 million to settle a class-action suit brought by other players, without admitting guilt. The judge in that case has so far refused to approve the settlement, saying it's not enough money. But the new lawsuit raises the scandal of concussions and dementia to another level. Dan Marino was known for throwing passes. Marino, from the shotgun. Reporter: And as a well-spoken NFL commentator, fronting lucrative commercials. I want fast relief and no odor. Reporter: Now, he, like the others filing suit, say he was affected by hits to the head. And this suit charges the NFL with turning a blind eye. And allowing players to block, tackle, butt, spear, ram and/or injure opposing players with their heads. The NFL has no comment on the lawsuit. I think the NFL is dealing with a scandal and an issue that is close to getting out of control. Reporter: Marino and the other players say not all their potential symptoms have surfaced. And the NFL should now pay for a medical monitoring program. They went above and beyond the settlement. Thanks very much. 15 years you played in the NFL. Hall of fame in August. Yeah. Dan Marino played 17 years. I'm sure at some point, he did get a concussion. I know for me, I banged up. And I was dinged up. But it was really my decision to go back in the game. And I think there's a lot different measures. If a guy shows any symptoms or signs, they do not let you re-enter the game. You helmet. It's a different T a & por talkeabout? Y cf1ine. To players the symptom of what it can do for future. When you a player in that &- you're not worried about'wha players are lainab they and they're now having these issues. Yeah. An I think somthin has to be done.- Sas T B T help guys who are suffering from effconcussions. I don't know I ev changes. Faster.

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